CVE-2026-68148fscrypt: Add missing superblock check in find_or_insert_direct_key()
- 7.8HighCVSS base score
- 0.09%Exploitation in 30 daysEPSS · top 100% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: fscrypt: Add missing superblock check in find_or_insert_direct_key() The legacy 'fscrypt_direct_keys' table caches master keys that are used by v1 encryption policies that have FSCRYPT_POLICY_FLAG_DIRECT_KEY. It's just a global table for all filesystems (since the keys can be provided by the legacy process-subscribed keyrings mechanism, which makes it difficult to reuse super_block::s_master_keys). The entries in it ('struct fscrypt_direct_key') do contain a super_block pointer, though, for passing to fscrypt_destroy_inline_crypt_key() when the last inode that references the key is evicted. However, when finding the fscrypt_direct_key for an inode, we weren't actually comparing the super_block pointer. As a result, inodes with different super_blocks could point to the same fscrypt_direct_key. That could extend the lifetime of a fscrypt_direct_key beyond the super_block it points to, causing a use-after-free later. Fix this by creating distinct fscrypt_direct_key structs for distinct super_block structs. Note that this problem doesn't exist in the v2 policy equivalent ("per-mode keys"), since the data structures there are per super_block.
Timeline
ID reserved
By Linux
- 11 days later
· 11 days later
Published
- 2 months later
· 2 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.09% · top 100% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < 965b5bc8cf5031225e057979ce660fec2bd5fbfc
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < 330249609b70778094a7a36f5b6bcfa6362121d4
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < deff41898a5ae3a47db5fa1896a494aa95efda5d
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < 95376fe9c145be35566991df99c53134943d992f
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < 466f187b501a5ac8e1ea2ccf3ccd5c46108d8830
- affected 22e9947a4b2ba255888541bd0111cf00b9b16586 – < b5fa40226e71c17847b9ff2816c6ca4133d0d994
- affected 6.1
- unaffected < 6.1
- unaffected 6.1.183 – ≤ 6.1.*
- unaffected 6.6.148 – ≤ 6.6.*
- unaffected 6.12.101 – ≤ 6.12.*
- unaffected 6.18.42 – ≤ 6.18.*
- unaffected 7.1.6 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References6
- https://git.kernel.org/stable/c/965b5bc8cf5031225e057979ce660fec2bd5fbfc (opens in a new tab)
- https://git.kernel.org/stable/c/330249609b70778094a7a36f5b6bcfa6362121d4 (opens in a new tab)
- https://git.kernel.org/stable/c/deff41898a5ae3a47db5fa1896a494aa95efda5d (opens in a new tab)
- https://git.kernel.org/stable/c/95376fe9c145be35566991df99c53134943d992f (opens in a new tab)
- https://git.kernel.org/stable/c/466f187b501a5ac8e1ea2ccf3ccd5c46108d8830 (opens in a new tab)
- https://git.kernel.org/stable/c/b5fa40226e71c17847b9ff2816c6ca4133d0d994 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-55533 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-68148)Record last updated .